GCN Circular 2919

E. Rykoff (U. Michigan) reports on behalf of the ROTSE collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia, 
responded to Swift GRB041228 (GCN #2918).  An automatic response was 
initiated during early twilight hours.  The first usable image was taken 
at 28 Dec 18:38:44 UT, 7.8 hours after the burst.  We took 50 60-s 
exposures before the burst position dropped below our minimum observing 
elevation.  The unfiltered images were calibrated relative to USNO A2.0. 
  Individual images have limiting magnitudes ranging from 17-18 as the 
sky darkened.    Comparison to DSS (second epoch) reveals no new sources 
within the 3-sigma error circle to a limiting magnitude of 18.8 for 
stacks of 10 images taken 8.4 hours after the burst.